Variable push rod for diesel



Patented A rize, 1 941 UNITED STATES PATENT OFFICE VARIABLE PUSH ROD FORDIESEL INJECTORS Lawrence J. Deeley, Blossvale, N. Y. v ApplicationApril 23, 1940, Serial No. 331,250 7 Claims. (Cl. 103-38) My inventionrelates broadly to fuel pump units for internal combustion engines, andmore particularly to variable push rod assemblies for the pump units.

An important object of my invention is to provide a push rod assemblywherein the connection between the push rod and the pump plunger isunique to permit the stroke of the plunger to be manually controlled toefiectively regulate the quantity of fuel supplied to the enginecylinder.

Another object of my invention is to provide a push rod assembly of theabove-mentioned character wherein the fuel injecting stroke of the pumpplunger is started at the same position of the engine piston for everyoperation thereof regardless of the adjustment of the assembly toregulate the distance that the plunger is set to travel, therebyassuring proper timing of the fuel injected into the engine cylindersfor'every speed of the engine.

Still another object of my invention is to provide a push rod assemblyof the above-mentioned character that is simple in its construction,inexpensive to manufacture and efficient and eflicacious in theperformance of its duties.

Other objects and advantages of my invention, will be apparent duringthe course of the following description.

In the drawingforming a part of this specificatiomand wherein likenumerals are employed to designate like parts throughout the same,

Figure 1 is a top plan view of a four-cylinder push rod assembly unit,

Figure 2 is a vertical sectional view of one of the push rod assemblies,

Figure 3 is a transverse sectional view taken on the line 3-3 of Figure2,

' Figure 4 is a fragmentary transverse sectional view taken on the line4-4 of Figure 2, and

Figure 5 is a fragmentary perspective view of a longitudinal section ofthe casing.

In the. accompanying drawing, wherein for the purpose of illustration,is shown a preferred embodiment of my invention, the numeral ldesignates a guide block which comprises a laterally extending integralpart of the engine having a channel I I in its outer vertical face, theside walls of which channels are grooved, as atl2, to receive the ribsI3 of the support M.

The support is adapted to carry a plurality of laterally spaced push rodassemblies l and each of the assemblies is adapted to be connected to afuel pump for separately injecting fuel into the cylinders of theengine. Each of the push rod assemblies is identical in its constructionand operation and a detailed description of but one will, therefore, begiven.

A guide plate l5 extends forwardly of the block 10 below the support [4and the square'portion l6 of the push rod I1 is snugly but slidablyaccommodated within the essentially square opening l8. The opening I3 isarranged directly above the cam shaft 2| of the engine and the lower endIQ of the push rod contacts the cam 20. pressed engagement with theperiphery of the cam by the coil spring-22 which is interposed betweenthe bottom face of the guide plate and a spring seat 23 carried by thelower end of the rod. The upper end 24 of the push rod extends asubstantial distance above the guide and in axial alignment with theinternal bore 25 of the casing 26 fixedly secured to the face 21 of thesupport by the bolts 28.

A pump plunger 29 is interposed between the pumpbarrel 30 and thecasing, the upper end of the plunger being formed with an enlarged headportion 3| arranged to reciprocate within the bore 32 of the barrel andthe lower end thereof being formed with an enlarged axially extendingsleeve 33 reciprocally received within the bore 25 of the casing. Thesleeve 33 is pro-, vided with laterally extending trunnions 34 whichnormally travel in longitudinally extending grooves 35 provided atopposite sides of the bore.

The grooves terminate adjacent the upper end of the bore 25 in anannular groove 31, said groove defining shoulders 36 which engage thetrunnions to limit the upward movement of the plunger relative to thecasing. The lower ends of the grooves 35 open directly through thebottom face of the casing and the upper ends thereof open directly intothe annular groove 31.

The internal bore 38 of the sleeve 33 is provided with a helical trackor thread 33 which receives the thread formed on the upper end 24 of thepush rod and, as clearly illustrated in Figure 2, the interfittingthreads 39 and 40 of the push rod and pump plunger have an essentiallysteep pitch. The threaded end of the push rod may be entirelyaccommodated by the bore 38, however, it is limited in the distancewhich it may be retracted therefrom to substantially the position asshown in Figure 2. It may thus be seen that the relation of the push rodwith the pump plunger is fixed at all times, but that the push rod maybe advanced into or retracted from the bore 38 to substantially vary thecombined length of the' plunger and push rod.

The outer face 21 of the support is formed with The rod is at all timesyieldably held in nular groove disposed adjacent the upper end of thebore, the saidplunger being normally held in fixed association with thepush rod by engagement of the trunnions within the longitudinal groovesbut adapted to rotate relative thereto upon move open into an annulargroove disposed-adjacent the upper end of the bore,a reciprocallyactuated push rod arranged below the pasmg'am having I an endscrew-threadedly received by* a recess opening through the lower e'ndofthe plunger, the said plunger being normally held in fixed associationwith the push rod by engagement of the trunnions within the longitudinalgrooves but adapted to rotate relative thereto upon movement of thetrunnions into register with the said annular groove, and meansindependent of the above-mentioned parts to move the casing axially ofthe said plunger.

6. A fuel pump having in combination, a supporting member, a tubularcasing carried by the said member, a plunger having trunnions adapted totravel in longitudinal grooves provided in the the upper end of thebore, an actuator means connected to the said support in a manner tomove the support and easing axially of the plunger, and a reciprocallyactuated push rod arranged below the casing and having an endscrewthreadedly received by a recess opening through the lower end ofthe plunger, the said plunger being normally held against rotation onthe push rod by engagement of the trunnions within the longitudinalgrooves of the casing but being adapted to rotate relative thereto uponmove ment of the trunnions into register with the annular groove.

.7. A fuel pump having in combination, a supporting member, a tubularcasing carried by the said member, a plunger having trunnions adapted totravel in longitudinal grooves provided in the bore of the casing whichlongitudinal grooves open into an annular groove disposed adjacent theupper end of the bore, an actuator means .associated with the saidsupport in a manner to move the support and easing axially of theplunger, a reciprocally actuated .push rod arranged below the casing andhaving an end screw-threadedly received by a recess opening through thelower end of the plunger, and means to reciprocally actuate the saidpush rod, the said plunger being normally held against rotation on thepush rod by engagement of the trunnions within the longitudinal groovesof the casing but being adapted to rotate relative thereto upon movementof the trunnions\into register with the annular grooves.

LAWRENCE J. DEELEY.

n a R R E J a Apr-5129,, E941 CUTTING AND WELDING TORCH Filed Aug. 22.,l

